To calculate the average speed for the entire trip, we need to consider the total distance traveled and the total time spent driving. The time spent eating lunch and buying gas does not contribute to the distance, so we only consider the driving time.

Step 1: Calculate the distance for each segment of the trip.

1. First segment:
   $\text{Distance} = \text{Speed} \times \text{Time}$ $= 84 \, \text{km/hr} \times \frac{24 \, \text{min}}{60} \, \text{hr} = 84 \times 0.4 = 33.6 \, \text{km}$

2. Second segment:
   $= 101 \, \text{km/hr} \times \frac{17 \, \text{min}}{60} \, \text{hr} = 101 \times 0.2833 = 28.6167 \, \text{km}$

3. Third segment:
   $= 50 \, \text{km/hr} \times \frac{48 \, \text{min}}{60} \, \text{hr} = 50 \times 0.8 = 40 \, \text{km}$

Step 2: Calculate the total distance.

$\text{Total Distance} = 33.6 + 28.6167 + 40 = 102.2167 \, \text{km}$

Step 3: Calculate the total driving time.

$\text{Total Time} = 24 \, \text{min} + 17 \, \text{min} + 48 \, \text{min} = 89 \, \text{min}$ Convert minutes to hours: $\text{Total Time} = \frac{89 \, \text{min}}{60} = 1.4833 \, \text{hours}$

Step 4: Calculate the average speed.

$\text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} = \frac{102.2167 \, \text{km}}{1.4833 \, \text{hours}} \approx 68.91 \, \text{km/hr}$

Thus, the average speed for the trip is approximately 68.91 km/hr.

Would you like any further details on this calculation or have any questions?

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Here are five related questions:

1. How would the average speed change if the person spent less time during the lunch break?
2. What is the impact of each driving segment on the overall average speed?
3. How does the choice of different constant speeds affect fuel efficiency?
4. Can we calculate the average velocity if the person returns to the starting point?
5. How would you convert the total distance traveled into miles?

Tip: When calculating average speed, always consider the total distance divided by the total time, regardless of the number of segments involved.